Around the world, three Facebook users die every minute. But their digital selves linger on in the photos, messages, likes and status updates they leave behind.

Most people haven’t given a second thought to what happens to their digital lives after death. In a recent survey by YouGov, only 20% of UK citizens have thought about what should be done with their online profile after they die.

It’s not just Facebook to consider. Think of all the emails, tweets, pictures, notes, documents, downloads – a lifetime’s worth of digital content left hanging in cyberspace – and the question of what to do with it when you pass on becomes a bit more serious. Think about everything you've ever written about in emails – how much do you want to share it with everyone?

That's why in April this year Google launched its inactive service manager – a new feature on all Google accounts that functions a bit like a digital will. The service allows users to choose what they would like to happen to their digital photos, documents and other virtual belongings held in Google-world. Google gives users the option of sharing their account data with a trusted friend or family member, or having their account deleted.

Beyond the grave

But it's not just privacy concerns that dominate conversations about post-death technology – now, more people are seeking the holy grail of immortality. Digitally, at least. In the old days, getting the chance to say your famous last words was a privilege limited to kings and convicts. Now anyone might be able to broadcast his or her final thoughts from beyond the grave.

If I Die First is a website that enables users to create a final message that will be published after they die. Similarly, the morbidly-named Death Switch is a service that prompts you for a password on a regular basis to check you are still alive. If it gets no response after several attempts, it will decide that you are either dead or seriously disabled, and send out a personal message from you to nominated friends and family. You can choose to add attachments to the email, and pass on your account details and final wishes.

If you want to be a bit more hands-on in the aftermath of your passing, apps like Legacy Organiser allow you to preplan your funeral, collecting videos, photos, songs and other information to be later shared with family and friends.

It doesn’t just stop after the final hymn. Some engravers are now inserting QR codes – a matrix barcode designed to encode large amounts of information – into headstones. When scanned with a smartphone or tablet the codes reveal a biography of the deceased and can even contain tributes from friends and family.

“If you think about a graveyard, it's a very static, ‘dead’ place,” says Elaine Cameron, a futurist at Burson-Marsteller. “Suddenly this technology has brought that location to life, and has brought the people resting there back to life.”

New algorithms are blurring the line between ‘dead’ and ‘alive’. By analyzing behaviour on social media sites, they are able to mimic your voice online, predicting what your next tweet or blog post might be.

“It’s going to become possible to analyse an entire life’s worth of content – the tweets, photos, videos and blog posts that we’re producing in such massive numbers,” Adam Ostrow, chief strategy officer at Mashable, theorized in a TED Talk in 2011. “As that happens it’s going to become possible for our digital personas to continue to interact in the real world, long after we’re gone.”

Services such as LivesOn are the first step down this road. With the catchy slogan “When your heart stops beating, you’ll keep tweeting”, LivesOn promises to impersonate you on twitter after your passing – perfect for social networking junkies.

Many futurists believe the ultimate aim for this technology is to create a virtual hologram of a deceased person – complete with all their thoughts and feelings uploaded onto a virtual ‘brain’ – which can be brought to life with the flick of a switch. For the past two years Dmitry Itskov, a 32 year-old Russian multimillionaire, has been planning to do just that. Dmitry’s Global Future 2045 initiative aims to "to create technologies enabling the transfer of an individual’s personality to a more advanced non-biological carrier,” by 2045. Meanwhile, companies such as LifeNaut are already offering people the ability to upload a “back-up” of their mind in preparation.

It's too early to tell how these technologies will change our attitude to death, or affect how we grieve and mourn lost loved ones. While we wait for some answers about the afterlife, its important to make every day count. The Tikker watch provides the ultimate momento mori – displaying the minutes and hours you have left on earth. But perhaps when death does come, it won’t be quite so final.